Electronic systems that can be worn on the body to monitor health parameters, store data and release drugs are reported in a study published online this week in Nature Nanotechnology.

Health-monitoring devices that continuously probe physiological activity are needed to understand and treat diseases such as Parkinson’s disease. However, the inability of existing devices to record and monitor data long term and deliver relevant therapies limits their usefulness.

Dae-Hyeong Kim and colleagues created a wearable electronic system that can perform monitoring, diagnostic and therapeutic tasks by integrating stretchable sensors, memory and actuators all made of nanomaterials. The team use silicon nanomembranes in the motion sensors, gold nanoparticles in the non-volatile memory and silica nanoparticles, loaded with drugs, in a thermal actuator. All these components are integrated on a stretchable patch that can be worn by patients on their skin, and resists stretching and bending.

Kim and colleagues demonstrate that the wearable system can measure and record muscle activity - the frequency of which is an important parameter to diagnose movement disorders - on a human wrist. The recorded data can then trigger the release of the therapeutic agents contained in the silica nanoparticles by means of the thermal actuator that lets the drug diffuse into the skin. A temperature sensor made of silicon nanomembranes monitors the skin temperature during delivery to prevent burns.